Forced HDR should allow mode switch on newer Macs to HDR even when specs would not allow it (high refresh rate, higher res scaled desktop), simplifying the current multi step way to circumvent these limitations.
Mixed HDR does a low level switch to HDR while leaving some subsystems of macOS thinking the desktop is still in SDR mode. This is useful for some video players like IINA which will use HDR anyway due to the increased headroom + this also allows brightness upscaling without requiring a full HDR mode switch.
When "Allow Forced HDR" is turned on, the main HDR switch for the display in the app menu root will also appear and allow HDR mode switch (while in previous versions the HDR switch appeared only when the user decreased the refresh rate or resolution to be within macOS constraints).
Forced HDR should allow mode switch on newer Macs to HDR even when specs would not allow it (high refresh rate, higher res scaled desktop), simplifying the current multi step way to circumvent these limitations.
Mixed HDR does a low level switch to HDR while leaving some subsystems of macOS thinking the desktop is still in SDR mode. This is useful for some video players like IINA which will use HDR anyway due to the increased headroom + this also allows brightness upscaling without requiring a full HDR mode switch.
When "Allow Forced HDR" is turned on, the main HDR switch for the display in the app menu root will also appear and allow HDR mode switch (while in previous versions the HDR switch appeared only when the user decreased the refresh rate or resolution to be within macOS constraints).